The present invention relates to electrical stringed instruments and signal processing circuits therefor that produce audio in an extended audio range, and, more particularly, to a signal processing circuit that allows a stringed instrument to produce audio in two or more audio ranges, and an electrical stringed instrument employing the signal processing circuit.
Conventional stringed instruments have a limited audio range. For example, the conventional six string guitar has a limited tonal spectrum and is able to achieve sounds above the lowest open string (when tuned at standard “A 440 Hz” the lowest open string, “E”), which vibrates at 82.41 Hz when plucked.
In the case of conventional guitars, while there is typically some overlap in the audio ranges of a lead guitar and a bass guitar, the lead guitar cannot produce the range that the bass guitar can produce. Consequently, it is common for many types of bands or musical groups to include a musician who plays lead guitar, and a second musician who plays bass guitar.
An alternative would be to provide a guitar with the six strings used for a lead guitar, and additional low end strings that would extend the range of the guitar into the range of a bass guitar. This would allow one musician to play bass and lead on the same guitar. However, it would be difficult, if not impossible, for such a guitar to produce the sound that can be produced by conventional lead and bass guitars played by different musicians. This type of guitar would also be extremely difficult to play, due to the presence of more than six independent strings.
Another alternative, represented by U.S. Pat. No. 4,481,854, is to suppress certain frequencies produced by the strings of a lead guitar in an attempt to selectively lower the range of the strings. This does not, however, produce true bass, in that the range of the sound produced by the strings is not actually shifted into a new range.
Accordingly, there is the need for an electrical stringed instrument with an extended audio range that allows a single performer to produce audio in two or more ranges, preferably from the same string or strings. Similarly, there is the need for an electric guitar that allows a single musician to produce sound in both bass and lead ranges from the same strings of the guitar.